Classification of Generalized Polarized Manifolds by Their Nef Values

نویسنده

  • MASAHIRO OHNO
چکیده

Let (M, E) be a generalized polarized manifold, i.e., a pair of an n-dimensional smooth projective variety and an ample vector bundle E of rank r on M . Let τ be the nef value of a polarized manifold (M, det E), i.e., the minimum of the set of real numbers t such that KM + tdet E is nef; we have τr ≤ n+ 1 by Mori’s theory. In this paper we classify the pairs (M, E) in the following two cases: (1) n− 2 ≤ τr and τ ≥ 1; (2) n+ 1− τr < τ ≤ 1.

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تاریخ انتشار 2005